Rotary engine oil metering pump

ABSTRACT

An internal combustion rotary engine is provided with an oil metering pump having an engine driven shaft with a chamber and an axial plunger that is spring biased to expand the chamber and is moved to contract the chamber by a follower that rotates with the pump shaft and operates against an engine throttle controlled roller to provide a plunger stroke that increases with increasing engine throttle opening and with the follower also having a timing port for periodically connecting an oil inlet port to the chamber during chamber expansion and then connecting the chamber during contraction to an outlet port to effect oil metering for rotor seal lubrication at a rate which increases with increasing engine speed and increasing throttle opening.

United States Patent 1191 1111 3,834,844 Morgan Sept. 10, 1974 1 ROTARY ENGINE OIL METERING PUMP 399,586 8/1924 Germany 417/461 [75] Inventor: Robert E. Mo gan, Grand ap ds, 170,229 l/l960 Sweden 417/461 Primary ExaminerC. J. I-Iusar Asslgneez General M9tors Corporation, Assistant Examiner-Leonard Smith Detl'olt, MlCh- Attorney, Agent, or FirmRonald L. Phillips [22] Filed: Mar. 8, 1973 21 Appl. NO.Z 339,393 1571 ABSTRACT An internal combustion rotary engine is provided with 52 us. c1 418/84 417/461 418/88 metering Pump having an engine drive" Shaft [51] i 29/02 with a chamber and an axial plunger that is spring bi- [58] 123/801 196 R; l84/26 ased to expand the chamber and is moved to contract 184/31 3 417/228 462 465 the chamber by a follower that rotates with the pump 418/84 88 6 shaft and operates against an engine throttle controlled roller to provide a plunger stroke that increases [56] References Cited with increasing engine throttle opening and with the follower also having a timing port for periodically con- UNITED STATES PATENTS necting an oil inlet port to the chamber during chamber expansion and then connecting the chamber dur- 1 or 9" ing contraction to an outlet port to effect oil metering ggg for rotor seal lubrication at a rate which increases with 3 435 914 4/1969 Arsum illliliill .....,.......III 123/196 R increasing engine Speed and increasing Home Open FOREIGN PATENTS OR APPLICATIONS Great Britain 417/461 3 Claims, 6 Drawing Figures ROTARY ENGINE OIL METERING PUMP This invention relates to rotary engine oil metering pumps and more particularly to an oil metering .pump that meters oil to lubricate the engine rotors gas seals in accordance with engine speed and throttle opening.

It is current practice to meter oil to lubricate arotary engines gas seals at a rate that increases with engine load. As is well known, this may be accomplished by metering the oil at a rate that increases with increasing engine speed and torque demand as indicated by engine throttle opening. While there are commercial pumps that presently produce such oil metering operation, there is a continuing effort for simplification and reduction in size of the pump coupled with enhanced reliability and reduction in cost.

The rotary engine oil metering pump according to the present invention is directed to such goals and comprises a pump body that is securable to the engines housing and has a bore in which a drive shaft is rotatably mounted. The shaft is driven by the engine and has a pin and slot drive connection with a follower. The drive shaft has a chamber which is expanded and contracted by reciprocation of an axial plunger that is mounted thereon and is spring biased to normally expand the chamber. The follower engages a roller that is rotatably mounted on one end of a shaft that is threaded to the pump body and is connected by a lever with the engine throttle linkage so that it is controlled with engine throttle opening to advance :and retract to operate on the follower during drive shaft rotation to in turn cause the plunger to contract the chamber once during each drive shaft revolution. Oil from the engines oil lubrication system is supplied to an inlet port in the pump body and an outlet port also in the pump body is provided for delivering oil meteredby the pump to lubricate the engine rotors gas seals, there being provided a timing port in the follower that periodically connects the inlet port and the outlet port with the chamber during expansion and contraction, respectively, during each revolution of the drive shaft. With the drive shaft and follower being driven at a speed proportional to engine speed and the stroke of the plunger increasing with increasing engine throttle opening under the control of the throttle controlled roller, oil is metered by the pump at a rate that increases with increasing engine speed and increasing throttle opening.

An object of the present invention is to provide a new and improved rotary engine oil metering pump.

Another object is to provide a rotary engine oil metering pump of improved structure that meters oil for rotor seal lubrication at a rate that increases with increasing engine speed and increasing engine throttle opening.

Another object is to provide a rotary engine oil metering pump having a plunger that is carried by an engine driven shaft and is stroked against a spring bias by a follower that rotates with the drive shaft and operates against an engine throttle controlled spherical roller that adjusts axially to provide increasing pump displacement with increasing engine throttle opening.

Another object is to provide a rotary engine oil metering pump having a drive shaft that has a chamber which is expanded and contracted by an axial plunger carried therewith which is spring biased to expand the chamber and is caused to contract the chamber by a controlled according to engine throttle opening with an oil inlet port communicating with the chamber during chamber expansion via a timing port in the follower with this timing port also communicating the chamber with an outlet port for delivery to the rotor seals during chamber contraction all within the same drive shaft revolution so that there is effected oil mete-ring for gas seal lubrication at a rate that increases with increasing engine speed and increasing engine throttle opening.

These and other objects of the present invention will become more apparent with reference to the following description and drawing in which:

FIG. 1 is an elevational view with parts shown diagrammatically and parts in section of a rotary engine with an oil metering pump according tothe present invention.

FIG. 2 is an enlarged view of the oil metering pump taken along the line 22 in FIG. 1.

FIG. 3 is a view of the oil metering pump taken along the line 3-3 in FIG. 2.

FIG. 4 is a view of the oil metering pump taken along the line 44 in FIG.2.

FIG. 5 is an enlarged view of the oil metering pump in FIG. 1.

FIG. 6 is a view of the oil metering pump taken alon the line 6-6 in FIG. 5.

Referring to FIG. 1, there is shown a rotary combustion enginel0 having an oil metering pump l2.according to the present invention that meters oil to lubricate the engine rotors gas seals. The engine l0 comprises a stationary outer body or housing 13 having a .rotor cavity that is defined by an inwardly facing peripheral wall 14 and a pair of opposed side walls 16, only one of which is shown. The peripheral wall 14 is in the shape of a two-lobed epitrochoid or a curve parallel thereto and a rotor 18 having the general shape of a triangle with three convex peripheral faces 20 is mounted within the rotor cavity on an eccentric 22 of a crankshaft 24 which is rotatably mounted outboard of the rotor cavity in the side walls 16. .An annular externally toothed gear 26 is received about and is concentric with the crankshaft 24 and is rigidly secured to the engine housing 13. The gear 26 meshes with an internally toothed gear 28 that is concentric with and fixed to one side of the rotor 18. The gear 28 has one and one-half times the number of teeth as the gear 26 with the result that this gearing enforces a fixed cyclic relation between the rotor and the crankshaft such that the crankshaft which is the engines output shaft makes three complete revolutions for every one complete revolution of the rotor. The rotor faces 20 cooperate with the peripheral wall 14 and with the side walls 16 to define three variable volume working chambers 30 that are spaced around and move with the rotor within the housing as the rotor orbits within the rotor cavity.

A carburetor 32 supplied with fuel from a fuel tank 34 by a pump 36 delivers an air-fuel mixture to an intake manifold 38 under the control of the carburetors throttle valve whose opening is controlled .by a throttle lever 40 that is connected at one end .of the throttle valves shaft 41. The other end of lever 40 is pivotally connected to a rod 42 that is linked to an accelerator pedal, not shown, for control by the vehicle operator,

the throttle valve arrangement being such that it is opened when the throttle lever 40 is pivoted in a counterclockwise direction as viewed in FIG. 1. The intake manifold 38 is connected in the engine housing 13 to deliver the air-fuel mixture to opposed intake ports 44, only one of which is shown, in the side walls 16. On rotor rotation in the direction indicated by the arrow in FIG. 1, air-fuel mixture is sequentially periodically admitted to the chambers 30 by the traversing motion of the rotors sides relative to the intake ports 44 whereafter the air-fuel mixture is trapped and then compressed in readiness for ignition. Sequential ignition of the airfuel mixture in the chambers 30 is effected by two spark plugs 46 and 48 which receive timed ignition pulses from a distributor 50 whose shaft 52 is driven by the crankshaft 24, this drive being effected by a pinion 54 which is secured to a mid-portion of the distributor shaft 52 and meshes with a worm gear 56 fixed on the crankshaft 24. The electrodes of the two spark plugs 46 and 48 are open to the chambers 30 through the peripheral wall 14 and are peripherally spaced thereabout so that the plug 46 is said to trail the other plug 48. The spark plugs 46 and 48 may be fired together or only one fired according to certain engine operating conditions as is well known in the art. With combustion, the peripheral wall 14 takes the reaction to force the rotor 18 to continue rotating and eventually each working chamber following the expansion phase is exhausted during the exhaust phase to an exhaust manifold 58 via an exhaust port 60 that is open to the rotor cavity through the peripheral wall 14 and is periodically traversed by the rotor apexes.

Sealing of the chambers 30 is effected by apex seals 62 each of which extends the width of the rotor and is mounted at a rotor apex, corner seals 64 each of which is mounted in a rotor side at each rotor apex, and side seals 66 each of which is mounted in a rotors side and extends between pairs of corner seals with the corner seals each providing a sealing link between the adjacent ends of two side seals and one apex seal. The apex seals 62 are urged radially outward by spring means, not shown, to continuously engage the peripheral wall 14 and both the corner seals 64 and side seals 66 on both rotor sides are urged axially outward by suitable spring means, not shown, to continuously engage the side walls 16. In addition, there is provided a circular oil seal 68 mounted in a concentric groove in each rotor side that is biased axially outward by suitable spring means, not shown, to continuously engage the opposite side wall 16 to prevent oil that is used for lubrication of the crankshaft and other rotating parts from moving radially outward to the gas seals.

The oil metering pump 12 according to the present invention is well suited to metering oil for delivery to this rotary engine via a gas seal lubrication system like that described in copending US. application Ser. No. 27 1 ,785, entitled Rotary Engine Gas Seal Lubrication System, filed July 14, I972, by James M. Casey. In this type of gas seal lubrication system the metered oil is supplied to a pair of oil feed ports 70, only one of which is shown, that are located in the side walls 16. The oil feed ports 70 are located opposite each other at the same radial and angular locations relative to the crankshaft axis and close to and past the side wall intake ports 44 in the direction of rotor rotation so that they are traversed or wiped by the rotor side seals during rotor motion the same as the side wall intake ports 44. With this arrangement the side wall oil feed ports feed oil onto the side walls as the side seals sequentially wipe therepast after having wiped past the side wall intake ports. Most of the oil thus delivered is wiped across the side walls and the remainder is'thrown by centrifugal force to lubricate the peripheral wall. For further details of such a gas seal lubrication system reference should be made to the aforementioned Casey patent application.

Describing now the oil metering pump 12 according to the present invention whose details are shown in FIGS. 2 through 6, there is a pump body 72 which at its upper end, as shown in FIGS. 3, 4 and 5, has a pilot land 74 which is fitted in a hole 75 in the underside of the engine housing 13. The pump body 72 is secured to housing 13 by a pair of bolts 76 with a gasket 77 being provided between the body and the housing to prevent leakage from the engine. The pump body 72 has a cylindrical bore 80 which extends centrally through the land 74, is closed at the opposite end and is aligned with the axis of the distributor shaft 52 as shown in FIG. 4. A short drive shaft 81 is rotatably supported along its cylindrical surface 82 in the upper end of the bore 80 and has formed at its upper end a rectangularlyshaped tongue 83 that is received in a correspondinglyshaped slot 84 in the lower end of the distributor shaft 52 whereby there is provided a drive connection between the distributor shaft 52 and the pumps drive shaft 81. A thrust ring 85 is retained by a snap ring 86 in a counter bore in the upper end of the pump body 72 and engages a shoulder 87 on the drive shaft to limit upward drive shaft movement. A follower member 90 having a cylindrical external surface 91 is rotatably mounted with a close fit in the pump body bore 80 beneath the drive shaft 81 and has bored from its upper end an axial bore 92 that receives with a close fit a reduced diameter portion 94 formed on the lower end of drive shaft 81. A pin 96 is pressed into a radial through-hole in the reduced diameter portion 94 of the drive shaft and is received in an openended axially extending slot 98 in the upper end of the follower member 90 as shown in FIGS. 3 and 4. The pin 96 and slot 98 provide a drive connection between the shaft 81 and the follower member 90 so that while the drive shaft rotates the follower, the follower is permitted to move axially relative to the drive shaft.

The pumps pumping mechanism is provided as best shown in FIG. 4 by the drive shaft 81 having a cylinder 100 which is bored from its reduced diameter end with its axis coincident with that of the drive shaft. Closely fitted in cylinder 100 is a solid cylindrical piston or plunger 101 which cooperates with the cylinder 100 and also with a radial cross-hole 102 with which the cylinder intersects at its upper end to define an expansible chamber 104 that expands and contracts when the plunger 101 is caused to reciprocate. A coil spring 105 is received about the exposed portion of the plunger 101 in cavity 103 between drive shaft 81 and follower 90 and at its upper end engages the lower end of the drive shaft 81 and at its lower end engages a spring seat 107 that is secured to the plunger 101 near its lower end whereby the spring acts to urge the plunger 101 downward against the closed end of the bore 92 in the follower 90 and the drive shaft 81 upward against the thrust ring 85.

Reciprocation of the plunger 101 while the drive shaft 81 is rotating is effected by the lower end of the follower 90 being formed with a flat cam surface 106 that is at an angle other than 90 with respect to the axis of the drive shaft 81 and follower 90 as shown in FIGS. 3 and 4. A throttle controlled stroke adjustment memher 108 is mounted for turning about an axis at right angles to that of the drive shaft 81 and the follower 90 in a bore 109 in the pump body 72 that intersects with the lower end of bore 80. The stroke adjustment member 108 has a land 110 near its outer end that is fitted in an enlarged diameter portion of bore 109 with there being provided an O-ring seal 111 in a groove in this land to prevent oil leakage outward of the pump body. The stroke adjustment member 108 is provided with a high lead threaded portion 112 that engages a correspondingly-threaded portion 114 of the bore 109 so that on turning of the stroke adjustment member causes it to move axially. A roller 115 having a spherical surface is journaled on a reduced diameter portion of the stroke adjustment member 108 and is retained thereon by a retaining ring 116. The spherical roller 115 is positioned in the bore 80 against the cam surface 106 of the follower 90 which is forced to always maintain contact therewith by spring 105. Thus, the spring 105 provides a retraction bias on the plunger 101 and also acts to maintain the follower 90 in contact with the spherical roller 115. With this arrangement and as the drive shaft 81 rotates, the follower 90 and plunger 101 reciprocate with the amount of plunger stroke being dependent upon the angle of the followers cam surface 106 and the radial position of its contact with roller 116. When the contact with the roller is coincident with the axis of the follower, there is zero plunger stroke and thus no chamber volume change. Alternatively, when this contact is at some radius from the axis of the follower the plunger 101 is forced to stroke upward by the follower 90 against the spring 105 as the cam surface 106 rides up the roller 115 during one-half of a follower revolution and then as it rides down the roller during the remaining half of a revolution the spring 105 retracts the plunger with the plunger stroke increasing as roller contact increases in radial distance from the axis of the follower. To assure that there are no pressure buildups that would inhibit such movement there is provided a passage 117 in the pump body 72 that is connected to vent cavities 118 and 119 to the engine with the cavity 103 vented through cavity 119 via a flat 120 and hole 121 on the follower 90 as shown in FIGS. 3, 4 and 6.

Axial adjustment of the roller 115 to change plunger stroke with change in engine throttle opening is provided by attachment of a lever 122 by staking to the outboard end of the stroke adjustment member 108 as shown in FIG. 4. A swivel 123 is secured to the lever 122 and slidably receives a rod 124 which has a retaining ring 125 secured thereto and receives a coil spring 126 between swivel 123 and retaining ring 125. The rod 124 is connected by a bowden wire 127 to a lever 128 which is pivotally supported on the carburetors throttle valve shaft 41 and is engaged by a tang 129 on the throttle lever 40 to pivot counterclockwise to pull the rod 124 as the throttle is opened as shown in FIG. 1. As best shown in FIG. 5, an adjustable stop provided by a screw 131 that is threaded to a flange on the stroke control lever 122 engages a portion 133 of the exterior of the pump body to determine the pumps minimum stroke condition which is described in more detail later, the desired position of the stop screw being fixed by a nut 134. The lever 122 is biased to the stop position by a torsion spring 135 which is arranged about the outboard portion of member 108 and engages at its opposite ends the pump body and the lever 122 so that its force urges clockwise movement of the lever as viewed in FIGS. 1 and 5. The coil spring 126 maintains the lever 128 at the carburetor against the tang 129 and also yields to permit the cable pulled rod 124 to slide in the swivel 123 when the rod is pulled beyond the maximum travel of the stroke control lever 122.

Describing now how oil is supplied to the pump 12, metered and then delivered to lubricate the engines gas seals, oil is obtained from the: engines pressurized lubrication system which includes; a passage 136 in the engine housing 13 as shown is FIG. 5. A drilled hole 138 in the pump body 72 is open at the pump base to the engines lubrication system passage 136 and connects at its other end with a port 140 that opens to the bore at the same axial location. as the radial passage portion 102 of the pump chamber 104 in the drive shaft 81. The chamber 104 is open at one radial end of passage 102 to a longitudinal slot 142 in the follower that is in turn open to an arcuate timing port 144 in the follower surface 91 that extends less than half-way therearound. The length of the slot 142 in the follower 90 is determined so that there is continuouscommunication between the timing port 144 and the chamber 104 as the plunger reciprocates relative to the drive shaft 81 throughout its range of varying stroke. The timing port 144 is registerable on follower rotation with the inlet port and then with a pair of outlet ports 146 and 148 in the pump body which intersect the bore 80 generally opposite the inlet port 140, the two outlet ports being located at the same angle on opposite sides of the diametral center line of the inlet port. Furthermore, the timing port 144 is located relative to the angle of the follower cam surface 106 and the direction of follower rotation so that as the plunger 101 strokes downward as viewed in FIG. 4 to expand the chamber 104, the timing port 144 is connecting the inlet port 140 to the chamber 104 and when the plunger is being stroked in the opposite direction to contract the chamber, the chamber is then connected by the timing port 144 first to the outlet port 146 and then to the outlet port 148 while the inlet port 140 is closed off so that oil is then forced into the outlet ports in equal amounts by the plunger. As shown in FIG. 6, the outlet ports 146 and 148 are open to oil outlet passages 152 and 154, respectively, in the pump body 72 which in turn are connected to deliver oil from the pump to lubricate the engines gas seals. For example, an oil pipe 156 connects the oil outlet passage 152 to supply oil to the side wall oil feed ports 70 as shown in FIG. 1, while another pipe 158 is available to'connect the other oil outlet passage 154 to supply the gas seals of another rotor where such separate oil metering is required in a two-rotor type engine of this type. It will also be understood that instead of lubrication via side wall feed ports, the oil may be delivered from the pump to the float bowl of the carburetor or may be delivered directly to the carburetors jet circuit or into the air stream in the carburetors throat to effect lubrication of the gas seals.

Describing typical oil metering operation provided by the oil metering pump 12, the pumps drive shaft 81 and the pin and slot connected follower 90 are driven from the engine crankshaft 24 via the distributor shaft 52 at a speed proportional to engine speed and with the engine throttle closed and the engine idling, the stroke control roller 115 is positioned at a minimum stroke condition determined by the setting of the stop screw 131. In this condition, the contact of the roller 115 with the cam surface 106 of follower 90 is at some minimum distance from the follower axis to thus determine minimum stroke of the follower 90. With oil made available to the pumps oil inlet port 140 and as the follower 90 turns in the direction indicated by the arrow in FIG. 6, the timing port 144 connects the inlet port 140 to the chamber 104 as it is being expanded by the plunger 101 following the follower 90 under the urging of the spring 105 with the roller 115 engaging the low side of the follower cam surface 106. Then on continued turning of the follower 90, the plunger 101 is forced by the follower riding the roller 115 to contract the chamber and the timing port 144 first comes into communication with the outlet port 146 and then with the other outlet port 148 while the inlet port 140 is blocked by the surface 91 off the follower from communicating with the chamber 104. At this minimum speed the small quantity of oil forced into the outlet ports is determined for the particular usage to meet the minimum oil requirements which occur at engine idle with no load demand. Then when the speed of the drive shaft 81 and follower 90 increases with increasing engine speed, irrespective of whether the engine throttle is opened, a greater number of shots of oil are delivered to the outlet ports 146 and 148 so that the oil delivered to these ports thus increase with increasing engine speed. On the other hand, for any constant speed of the drive shaft 81 and follower 90 and on an increase in throttle opening, the lever 122 turns as the engine throttle is opened to position the roller 115 at proportionately greater distances from the axis of the follower so that the pump stroke similarly increases and thus the amount of oil that is discharged to the outlet ports 146 and 148 with such increase occurring up until full engine throttle opening is reached. Thus, oil is metered to the outlet ports 146 and 148 at a rate which increases with both increasing pump drive shaft and follower speed which is proportional to engine speed and increasing plunger stroke which is proportional to engine throttle opening whereby the oil is thus metered at a rate which increases with both increasing engine speed and throttle opening and thus with engine load.

It will also be understood that for engines where only one metered oil supply is required, the pump is easily adapted thereto by simply connecting one of the outlet ports back to the inlet port or by having a single outlet port opposite the inlet port. Furthermore, it will be understood that the oil supplied to the pump may be by gravity feed instead of by engine lubrication pressure.

The above described embodiments are illustrative of the invention which may be modified within the scope of the appended claims.

I claim:

1. An oil metering pump for metering oil to lubricate a rotary engine having gas seals, an output shaft and a throttle comprising a pump body having a bore, a pump drive shaft rotatably mounted in said bore, means drivingly connecting said output shaft to rotate said pump drive shaft, a follower rotatably mounted in said bore, said follower having a bore with a closed inner end, said pump drive shaft having a reduced diameter portion received in said bore in said follower, means for drivingly connecting said pump drive shaft and said follower while permitting said follower to move axially in said bore relative to said pump drive shaft, said pump drive shaft having a central axially extending cylinder in one end thereof, a double-ended plunger of constant diameter mounted in said cylinder, one end of said plunger projecting out of said cylinder to engage said closed end of said bore in said follower, the other end of said p e and sai y n tzcrativglly efining? chamber in said pump drive shaft whose volume varies when said plunger is reciprocated, a stroke adjustment member mounted in said pump body, a roller rotatably supported on said stroke adjustment member, said follower having a cam surface engageable with said roller and cooperating therewith to effect movement of said plunger in one direction to contract said chamber during a portion of a follower revolution and permitting said plunger to move in the opposite direction to expand said chamber during the remainder of the follower revolution with the stroke of said plunger increasing as the location of contact of said roller with said follower is increased from the axis of said follower, a spring seat secured to said plunger adjacent said one end thereof, spring means arranged in said bore in said follower between said one end of said pump drive shaft and said spring seat for maintaining said plunger against said follower while forcing said follower to follow said roller during movement of said plunger in said opposite direction, an inlet port in said pump body opening through said bore for supplying oil to said chamber, an outlet port in said pump body opening through said bore for delivering oil from said chamber to lubricate said gas seals, a timing port in said follower member for alternatively connecting said inlet port to said chamber during chamber expansion and said outlet port to said chamber during chamber contraction all during each revolution of said pump drive shaft, means for operatively connecting said throttle and said stroke adjustment member so that said stroke adjustment member is moved to increase the stroke of said plunger as said throttle is opened whereby oil is metered from said inlet port to said outlet port for gas seal lubrication at a rate which increases with increasing output shaft speed and increasing throttle opening.

2. An oil metering pump for metering oil to lubricate a rotary engine having gas seals, an output shaft and a throttle comprising a pump body having a bore, a pump drive shaft rotatably mounted in said bore, means drivingly connecting said output shaft to rotate said pump drive shaft, a follower rotatably mounted in said bore, said follower having a bore with a closed inner end, said pump drive shaft having a reduced diameter portion received in said bore in said follower, means for drivingly connecting said pump drive shaft and said follower while permitting said follower to move axially in said bore relative to said pump drive shaft, said pump drive shaft having a central axially extending cylinder in one end thereof, a double-ended plunger of constant diameter mounted in said cylinder, one end of said plunger projecting out of said cylinder to engage said closed end of said bore in said follower, the other end of said plunger and said cylinder cooperatively defining a chamber in said pump drive shaft whose volume varies when said plunger is reciprocated, a stroke adjustment member mounted in said pump body, a roller rotatably supported on said stroke adjustment member, said follower having a cam surface engageable with said roller and cooperating therewith to effect movement of said plunger in one direction to contract said chamber during a portion of a follower revolution and permitting said plunger to move in the opposite direction to expand said chamber during the remainder of the follower revolution with the stroke of said plunger increasing as the location of contact of said roller with said follower is increased from the axis of said follower, a spring seat secured to said plunger adjacent said one end thereof, spring means arranged in said bore in said follower between said one end of said pump drive shaft and said spring seat for biasing said plunger to follow said follower in the opposite direction while also biasing said follower to follow said roller during movement of said plunger in said opposite direction, an inlet port in said pump body opening through said bore for supplying oil to said chamber, an outlet port in said pump body opening through said bore for delivering oil from said chamber to lubricate said gas seals, a timing port in said follower for alternatively connecting said inlet port to said chamber during chamber expansion and said outlet port to said chamber during chamber contraction all during each revolution of said pump drive shaft, means for causing said stroke adjustment member to move to adjust the contact location of said roller when said stroke adjustment member is turned, means for operatively connecting said throttle and said stroke adjustment member so that said stroke adjustment member is turned to increase the stroke of said plunger as said throttle is opened whereby oil is metered from said inlet port to said outlet port for gas seal lubrication at a rate which increases with increasing output shaft speed and increasing throttle opening.

3. An oil metering pump for metering oil to lubricate a rotary engine having gas seals, an output shaft and a throttle comprising a pump body having a bore, a pump drive shaft rotatably mounted in said bore, said follower having a bore with a closed inner end, said pump drive shaft having a reduced diameter portion received in said bore in said follower, means drivingly connecting said output shaft to rotate said pump drive shaft, a follower having an external cylindrical surface rotatably mounted in said bore, means for drivingly connecting said pump drive shaft and said follower while permitting said follower to move axially in said bore relative to said pump drive shaft, said pump drive shaft having a central axially extending cylinder in one end thereof, a double-ended plunger of constant diameter mounted in said cylinder, one end of said plunger projecting out of said cylinder to engage said closed end of said bore in said follower, the other end of said plunger and said cylinder cooperatively defining a chamber in said pump drive shaft whose volume varies when said plunger is reciprocated, a stroke adjustment member mounted in said pump body, a spherical roller supported on said stroke adjustment member for rotation about an axis that intersects with the axis of said fol lower, said follower having a flat cam surface inclined to the axis of said follower engageable with said roller and cooperating therewith to effect movement of said plunger in one direction to contract said chamber during a portion of a follower revolution and permitting said plunger to move in the opposite direction to expand said chamber during the remainder of the follower revolution with the stroke of said plunger increasing the location of contact of said roller with said follower is increased in a radial direction from the axis of said follower, a coil spring arranged in said bore in said follower about said plunger and between said one end of said pump drive shaft and said spring seat for biasing said plunger to follow said follower in the opposite direction while also biasing said follower to follow said roller during movement of said plunger in said opposite direction, an inlet port in said pump body opening through said bore for supplying oil to said chamber, an outlet port in said pump body opening through said bore for delivering oil from said chamber to lubricate said gas seals, a timing port in said follower through said cylindrical surface for alternatively connecting said inlet port to said chamber during chamber expansion and said outlet port to said chamber during chamber contraction all during each revolution of said pump drive shaft, means for causing said stroke adjustment member to move to adjust the contact location of said roller when said stroke adjustment member is turned, means for operatively connecting said throttle and said stroke adjustment member so that said stroke adjustment member is turned to increase the stroke of said plunger as said throttle is opened whereby oil is metered from said inlet port to said outlet port for gas seal lubrication at a rate which increases with increasing output shaft speed and increasing throttle opening. l 

1. An oil metering pump for metering oil to lubricate a rotary engine having gas seals, an output shaft and a throttle comprising a pump body having a bore, a pump drive shaft rotatably mounted in said bore, means drivingly connecting said output shaft to rotate said pump drive shaft, a follower rotatably mounted in said bore, said follower having a bore with a closed inner end, said pump drive shaft having a reduced diameter portion received in said bore in said follower, means for drivingly connecting said pump drive shaft and said follower while permitting said follower to move axially in said bore relative to said pump drive shaft, said pump drive shaft having a central axially extending cylinder in one end thereof, a doubleended plunger of constant diameter mounted in said cylinder, one end of said plunger projecting out of said cylinder to engage said closed end of said bore in said follower, the other end of said plunger and said cylinder cooperatively defining a chamber in said pump drive shaft whose volume varies when said plunger is reciprocated, a stroke adjustment member mounted in said pump body, a roller rotatably supported on said stroke adjustment member, said follower having a cam surface engageable with said roller and cooperating therewith to effect movement of said plunger in one direction to contract said chamber during a portion of a follower revolution and permitting said plunger to move in the opposite direction to expand said chamber during the remainder of the follower revolution with the stroke of said plunger increasing as the location of contact of said roller with said follower is increased from the axis of said follower, a spring seat secured to said plunger adjacent said one end thereof, spring means arranged in said bore in said follower between said one end of said pump drive shaft and said spring seat for maintaining said plunger against said follower while forcing said follower to follow said roller during movement of said plunger in said opposite direction, an inlet port in said pump body opening through said bore for supplying oil to said chamber, an outlet port in said pump body opening through said bore for delivering oil from said chamber to lubricate said gas seals, a timing port in said follower member For alternatively connecting said inlet port to said chamber during chamber expansion and said outlet port to said chamber during chamber contraction all during each revolution of said pump drive shaft, means for operatively connecting said throttle and said stroke adjustment member so that said stroke adjustment member is moved to increase the stroke of said plunger as said throttle is opened whereby oil is metered from said inlet port to said outlet port for gas seal lubrication at a rate which increases with increasing output shaft speed and increasing throttle opening.
 2. An oil metering pump for metering oil to lubricate a rotary engine having gas seals, an output shaft and a throttle comprising a pump body having a bore, a pump drive shaft rotatably mounted in said bore, means drivingly connecting said output shaft to rotate said pump drive shaft, a follower rotatably mounted in said bore, said follower having a bore with a closed inner end, said pump drive shaft having a reduced diameter portion received in said bore in said follower, means for drivingly connecting said pump drive shaft and said follower while permitting said follower to move axially in said bore relative to said pump drive shaft, said pump drive shaft having a central axially extending cylinder in one end thereof, a double-ended plunger of constant diameter mounted in said cylinder, one end of said plunger projecting out of said cylinder to engage said closed end of said bore in said follower, the other end of said plunger and said cylinder cooperatively defining a chamber in said pump drive shaft whose volume varies when said plunger is reciprocated, a stroke adjustment member mounted in said pump body, a roller rotatably supported on said stroke adjustment member, said follower having a cam surface engageable with said roller and cooperating therewith to effect movement of said plunger in one direction to contract said chamber during a portion of a follower revolution and permitting said plunger to move in the opposite direction to expand said chamber during the remainder of the follower revolution with the stroke of said plunger increasing as the location of contact of said roller with said follower is increased from the axis of said follower, a spring seat secured to said plunger adjacent said one end thereof, spring means arranged in said bore in said follower between said one end of said pump drive shaft and said spring seat for biasing said plunger to follow said follower in the opposite direction while also biasing said follower to follow said roller during movement of said plunger in said opposite direction, an inlet port in said pump body opening through said bore for supplying oil to said chamber, an outlet port in said pump body opening through said bore for delivering oil from said chamber to lubricate said gas seals, a timing port in said follower for alternatively connecting said inlet port to said chamber during chamber expansion and said outlet port to said chamber during chamber contraction all during each revolution of said pump drive shaft, means for causing said stroke adjustment member to move to adjust the contact location of said roller when said stroke adjustment member is turned, means for operatively connecting said throttle and said stroke adjustment member so that said stroke adjustment member is turned to increase the stroke of said plunger as said throttle is opened whereby oil is metered from said inlet port to said outlet port for gas seal lubrication at a rate which increases with increasing output shaft speed and increasing throttle opening.
 3. An oil metering pump for metering oil to lubricate a rotary engine having gas seals, an output shaft and a throttle comprising a pump body having a bore, a pump drive shaft rotatably mounted in said bore, said follower having a bore with a closed inner end, said pump drive shaft having a reduced diameter portion received in said bore in said follower, means drivingly connecting said output shaft to rotate said pump drive shaft, a follower having an external cylindrical surface rotatably mounted in said bore, means for drivingly connecting said pump drive shaft and said follower while permitting said follower to move axially in said bore relative to said pump drive shaft, said pump drive shaft having a central axially extending cylinder in one end thereof, a double-ended plunger of constant diameter mounted in said cylinder, one end of said plunger projecting out of said cylinder to engage said closed end of said bore in said follower, the other end of said plunger and said cylinder cooperatively defining a chamber in said pump drive shaft whose volume varies when said plunger is reciprocated, a stroke adjustment member mounted in said pump body, a spherical roller supported on said stroke adjustment member for rotation about an axis that intersects with the axis of said follower, said follower having a flat cam surface inclined to the axis of said follower engageable with said roller and cooperating therewith to effect movement of said plunger in one direction to contract said chamber during a portion of a follower revolution and permitting said plunger to move in the opposite direction to expand said chamber during the remainder of the follower revolution with the stroke of said plunger increasing as the location of contact of said roller with said follower is increased in a radial direction from the axis of said follower, a coil spring arranged in said bore in said follower about said plunger and between said one end of said pump drive shaft and said spring seat for biasing said plunger to follow said follower in the opposite direction while also biasing said follower to follow said roller during movement of said plunger in said opposite direction, an inlet port in said pump body opening through said bore for supplying oil to said chamber, an outlet port in said pump body opening through said bore for delivering oil from said chamber to lubricate said gas seals, a timing port in said follower through said cylindrical surface for alternatively connecting said inlet port to said chamber during chamber expansion and said outlet port to said chamber during chamber contraction all during each revolution of said pump drive shaft, means for causing said stroke adjustment member to move to adjust the contact location of said roller when said stroke adjustment member is turned, means for operatively connecting said throttle and said stroke adjustment member so that said stroke adjustment member is turned to increase the stroke of said plunger as said throttle is opened whereby oil is metered from said inlet port to said outlet port for gas seal lubrication at a rate which increases with increasing output shaft speed and increasing throttle opening. 